pre detination, rough idle, spark plugs?

[IanS]

Ive got a redtop sr with fmic, walbro, stock injectors and stock turbo I just made the swich from NGK BKR 7s to BKR 7 iridiums, they were great for a couple days, but now it detonates at anything above 9 psi and feels genraly like crap, is this because of the new plugs, or somthing else, I was running about a .030 gap on the old plugs, and I didnt think you needed to gap iridium plugs so I left them as is, also, could it have somthing to do with my spark timing, ive been trying to figure out how many degrees btdc I should set it too. Any help would be great.

Thanks

[Blown240sx]

You have to gap the Iridums also. Just b careful when doing it because they can chip very easily. Your detonation is probably cause the plugs are gapped to wide and getting blown out by incoming air or exhuast exiting.

[S13FASTBACKSR]

You have to gap the Iridums also. Your detonation is probably cause the plugs are gapped to wide and getting blown out by incoming air or exhuast exiting.

also the timing should be 15degrees btdc (second mark from the right)

[hpmachine]

yes you need to gap those suckers! they come gapped at like .70 or some ridiculous number...

[slow s13]

just to let you know thats not pre detonation, that just normal detonation, if you get pre detonation you get holes in pistons and blown head gaskets

[IanS]

yes your right slow, I get all hot and bothered when my car runs like crap hahaha, good good my timing is correct, I guess Ill have to gap those plugs when I get home from ojibwe forests prorally Bemidji MN here I come